The black sunflower stem weevil, Apion occidentale (Fall) Feeding damage is seldom significant, but the weevil has been associated with the transmission of the pathogen, Phoma macdonaldii Boerma, the causal agent of Phoma black stem. In recent years, severe pitting on cotyledons or seedling sunflower has been observed and resulted in some occasional stand loss. In most cases, damage from the black sunflower stem weevil has been non-economic.